Device for connecting pipelines

ABSTRACT

Device for aligning connection of pipelines, comprising a male part having at least one guide pin with tapered end and a male part having at least one correspondingly shaped receiving groove, so that the male and the female part, each mounted on its pipeline end, can be joined together with aligning effect so that the ends of the pipelines are connected. The device is distinguished in that it further comprises: at least one bolt, arranged parallel to the longitudinal axis of the at least one pair of guide pin and receiving groove, said bolt being provided with means for lifting of bolts, controlled tensioning and long-term stable locking, and optionally a means for rapid release, and sealing, in the form of a single, double or multiple barrier, for sealing on opposing sealing faces on the male and the female part, placed so that the seal envelops the ends of the pipelines as connected.

FIELD OF INVENTION

The present invention relates to devices for connecting pipelines. Morespecifically, the invention concerns devices for alignment andconnecting pipelines the ends of which may be mutually movable prior toconnecting and thus not aligned. The device may be used for repeatedconnection/disconnection of pipelines.

BACKGROUND OF THE INVENTION AND PRIOR ART

Devices for connecting and disconnecting pipelines are advantageouslyplaced in pipelines for transferring fluid from for example a productionplatform or a storage place to a transport vessel. This may be desirablefor security reasons, for example when the drift of the vessel is toolarge or the rotation is too large, with risk both with regard tohealth, environment and values, or owing to functional advantages byhaving a connectable/disconnectable coupling in a pipeline.

A device for connecting pipelines has advantageously functionality forconnection and disconnection even at relatively large movements betweenthe end of the pipelines, both in the form of rotation, radial andangular movement. In some situations it will be of great significancefor the security if a device for connecting pipelines may bedisconnected quickly. It can also be advantageous if connection anddisconnection can be carried out with remote control without need formanual operations.

There are many devices for connecting pipelines. However, disadvantagesare to a varying degree attached to the previously known devices. Someexamples of such disadvantages are as follows:

-   -   Often there is not sufficient control with pretensioning or        tightening moment for connected pipelines.    -   In many cases there will be a change with time of said        tightening moments due to wear and tear or other break down        mechanisms with possibly resulting leakage and danger to people,        environment and values.    -   In many cases the tool for pretensioning bolts will not be        permanently integrated in the connecting device, which means        that part of the connecting operation as a whole must be carried        out manually. This also influences the time for connecting and        disconnecting.    -   For many devices there is no possibility of rapid disengagement,        which might be an absolute requirement in some connections,        particularly for security reasons.    -   Several couplings have only one barrier for sealing between the        pressure in the pipeline and the external environment.    -   For connecting devices with two barriers in the seal it is as a        rule only possible to pressure test the connection as a whole,        i.e. it cannot be securely detected whether both barriers are        tight.    -   Some connecting devices are very sensitive with respect to        relative movement which may be accepted between the ends of the        pipeline, which is conducive to narrow margins which may be        accepted prior to the coupling together.

There is demand for a device for connecting pipelines, the device havingimproved properties with respect to the above-mentioned problems.

SUMMARY OF THE INVENTION

By means of the present invention the above-mentioned demand is met inthat there is provided a device for aligning connection of pipelines,comprising a male part having at least one guide pin with tapered endand a female part having at least one correspondingly shaped receivinggroove such that the male and the female part, each mounted on itspipeline end, may be joined together with aligning effect such that theends of the pipeline are connected, the device being distinguished inthat it further comprises:

at least one bolt located parallel to the longitudinal axis of the atleast one pair of guide pin and receiving groove, said bolt beingprovided with means for controlled tensioning and long-term stablelocking, and, if desired, a means for rapid release, and

sealing in the form of a single, double or multiple barrier, for sealingopposing sealing faces on the male an d the female part, arranged sothat the seal envelops the ends of the pipeline as coupled together.

With coupling together of the ends of the pipelines it is also meantthereby that the extension of the ends of the pipeline, with opening fortransport of fluid through the device, is becoming connected. By thephrase “the seal envelops the ends of the pipeline” it is also meantthat the seal encloses the opening for transport of fluid through thedevice. The female and male parts of the device are preferably mountedas an extension on each of their pipeline ends, with flanges, however,the device may also be so shaped such that the ends can be securedinside the device.

The device according to the invention most preferably comprises twopairs of guide pins and receiving grooves, with a threaded bolt in thecenter axis of each pair of guide pin and receiving groove. Saidembodiment is preferred for most pipe sizes.

The device according to the invention preferably comprises, particularlyfor large pipe sizes, four pairs or more of guide pins and receivinggrooves, with a threaded bolt in the center axis of each pair of guidepin and receiving groove. Increased pipe size makes it more advantageouswith several pairs of guide pins and receiving grooves, preferably withone bolt for each pair.

The device according to the invention may for small pipes preferablycomprise one pair of guide pin and receiving groove, with a threadedbolt or swan socket between the pipeline and the one pair of guide pinand receiving groove.

The means for controlled tensioning of bolts and lifting of bolts ispreferably of hydraulic type, with one means for each bolt.

The device preferably comprises a means for rough turning of either themale or the female part about one pipeline axis, such that the guidepins and receiving grooves may be essentially aligned with respect torotation.

The device further advantageously comprises a means for pressure testingof the seals, in the form of a nipple and grooves to each room betweenthe seals, however, for one barrier seals to between the innermost sealand the pipeline, connected to hydraulic equipment.

The female part preferably comprises, from the center axis and radiallyoutwards, opening for transport of fluid, a hub shaped symmetricallyaround the opening, receiving grooves adapted to the guide pins of themale part, guide edges and external skirt, the hub, the receivinggrooves and the guide edges contributing to the aligning effect whenjoining the female and the male part. Thus, the male and the femalepart, for the sides to be joined, are shaped as tapered guide pins,guide edges and hubs which fit into correspondingly shaped grooves sothat the alignment increases as the parts are joined together.

DRAWINGS

FIG. 1 shows a section of the device according to the invention, priorto the coupling together.

FIG. 2 shows the device coupled together.

FIG. 3 shows the bolts driven down in position below the lower flange.

FIG. 4 shows the bolts turned to lockable position, hydraulicallypretensioned.

FIG. 5 shows the pretension mechanically secured.

FIG. 6 shows activated rapid release.

FIG. 7 shows an alternative rapid releaser, and

FIG. 8 shows another embodiment of the device according to the inventionfor connecting the lower and upper part.

DETAILED DESCRIPTION

For the device according to the present invention hydraulicpretensioning of the bolts is preferably used, followed by mechanicallocking by means of for example lock nuts. It is possible to use a verysubstantial force of contraction, which makes it possible for largegasket diameters and standard flange couplings, and, moreover, use ofseveral seal barriers in the gasket system, for example 2 barriers ormore.

In the device according to the invention the tool for pretensioning ormake-up of the bolts is permanently attached, with one tool for eachbolt, which enables a completely remotely operated coupling with goodcontrol of the make-up torques. Preferably, there is also included ahydraulically activable rapid release, such that the sometimes verystrict requirement to maximum allowable disconnecting time can be met.

The device for connecting pipelines according to the invention canaccept relatively large relative movements between the two pipeline endsand the two main parts of the device, both in the form of rotation andradial and angular movements. This is obtained by using advantageousgeometries which are conducive thereto that the aligning effect becomessubstantial, both with respect to rotation and radial and angulardisplacement. Accordingly, when the two main parts of the couplingapproach each other during the connecting process, the main parts andthe ends of the pipelines will become aligned as the parts are beingcoupled together, whereby the maximum allowed misfit between the ends ofthe pipelines prior to coupling together is relatively large. Saidaligning takes place without overloading any parts of the deviceaccording to the invention mechanically, which is obtained through acombination of the shape of the device and the dimensioning of thedevice.

The male and female part of the device, mounted on each of theirpipeline end, must be brought into reasonable engagement by means ofother equipment before the coupling together with the device may takeplace.

Reference is now made to FIG. 1 which illustrates a device according tothe invention, with two guide pins 6, 2 and two receiving grooves 1, 8,7. The device consists of two main parts, viz. a female part 9 and amale part 10. In the female part 9 there are holes for the bolts 3 whichhave been mounted into a pretensioning tool 4, 5 for the bolts locatedin the male part 10. The bolts can be moved up and down by means of abolt lifter which is part of a tool 4, 5 for make-up of the bolts andare turned by means of a turning motor which turns the bolt lifter, thebolt and an optional rapid releaser 12. In this position the bolts 3 areparked in a radial guide 6 integrated in the guide pins. The bolt can beprovided with threads or, more simply, with swan socket or hooks (as itappears from further figures). Correspondingly, in the lower main part,the female part 9, holes are arranged either with threads or adaptedgrooves.

A guide edge 8 in the female part has a saw-toothed profile with two ormore teeth. Correspondingly, on the upper part of the device, on theguide pin, a directional guide 2 is arranged which may be a radiallymounted pin or saw teeth corresponding to the guide edge 8 mounted inthe female part of the device. The guide edge 8 may either be shapes asa complete triangle (as shown in section A-A) for fluid couplings withentirely passive control of the relative direction of rotation of thetwo main parts or with cut-off teeth where a motor for the initialrotation is used, after which the guide edge successively takes over forfine adjustment of the rotation. The purpose of the rotation devices isto ensure that the bolts in the upper part of the device, as illustratedin the male part, will be essentially aligned with the holes in thelower part of the device, i.e. the holes in the female part. Around thecenter of the fluid connection there is a conical hub 1 which can havean upper and lower guide edge for radial control with respect to theguide 6. The upper and lower guide edge will together give alignment ofthe radial guide 6 with respect to the hub 1. Said hub corresponds to aspecially shaped hub or flange. A corresponding alignment effect can beobtained by means of axial contact between an upper flange 10 and anexternal skirt 7 in combination with only one radial guide edge on hub1.

The lower part 4 of the pretensioning tool is mounted in the male part,on an upper flange. This tool consists of a hydraulic part forpretensioning or make-up of the bolt when it has come into position.Further, a lock nut or a locking device is also included so that thehydraulic may be uncoupled or relieved without loosing the pretension.Such tools are known from pretensioning of flanges and are commerciallyavailable.

At the top of the upper part 5 of the bolt pretensioning tool a rapidreleaser 12 is illustrated which can be used in systems where very rapiduncoupling is required. According to the further figures this ishydraulically activated by means of a cylinder in the center of theextension of the bolt. The rapid release causes the bolt to loose theinitial tension momentarily and to loose the engagement with the lowermain part of the device. Thus, the bolts are suspended or fastened inthe rapid releaser.

The gaskets 11 provide seating between the upper flange 10 of the malepart and the hub 1 in the female part when the main parts of the devicehave been completely joined together. The gaskets 11 can be both axiallyand radially arranged.

In FIG. 2 the device according to the invention has been illustratedjoined together.

In FIG. 3 the bolts are shown driven down into position below the lowerflange 9 of the female part, and in section below the lower flange thebolts are illustrated in unlocked position.

In FIG. 4 the bolts have been turned to locked position andhydraulically pretensioned with the piston on the lower part 4 of thebolt pretensioning tool against the upper flange 10 of the male part.

In FIG. 5 it is shown that the pretensioning is mechanically secured bya lock nut, with the hydraulic released.

In FIG. 6 an activated rapid releaser 12 is shown whereas in FIG. 7 analternative rapid releaser 12 is shown.

In FIG. 8 the device according to the invention is illustrated withalternative control for connecting the two main parts and thereby theends of the pipelines. The illustrated embodiment has two radial controlgrooves on the hub 1 which provide for both radial and axial alignment.

1. Device for aligning the connection of pipelines, comprising: a malepart that is mounted on an end of a first one of the pipelines and thathas at least one guide pin, which has a tapered end; a female part thatis mounted on an end of a second one of the pipelines and that has atleast one receiving groove shaped to receive the male part, each guidepin and corresponding receiving groove forming a pin-groove pair havinga respective, common longitudinal axis when the first and secondpipelines are joined, at least one bolt, arranged parallel to thelongitudinal axis of the at least one pin-groove pair, said bolt beingequipped with means for controlled tensioning and long-term stablelocking of the bolt, at least one seal sealing opposing sealing faces onthe male and female part, and enveloping the ends of the pipelines whenthe pipelines are connected.
 2. Device according to claim 1, in which:the device comprises two pin-groove pairs; and each bolt is a threadedbolt positioned in and extending along a center axis of a respectivepin-groove pair.
 3. Device according to claim 1, in which: the devicecomprises four pin-groove pairs; and each bolt is a threaded boltpositioned in and extending along a center axis of a respectivepin-groove pair.
 4. Device according to claim 1, in which: the bolt islocated between the pin-groove pair and the pipelines when the pipelinesare connected.
 5. Device according to claim 1, in which the means forcontrolled tensioning of the bolt(s) is hydraulic with one means forcontrolled tensioning being provided for each bolt.
 6. Device accordingto claim 5, in which the means for controlled tensioning of the bolts isalso provided for lifting and lowering of the bolts.
 7. Device accordingto claim 1, further comprising means for turning about one pipeline axisof either the male or the female part so that the guide pins and thereceiving grooves can be at least approximately aligned with respect torotation.
 8. Device according to claim 1, further comprising a means,coupled to hydraulic equipment, for pressure testing of the seal(s), inthe form of a nipple and groove for each space between the seal(s) wherea plurality of seals is provided and between the innermost portion ofthe seal and the pipeline where only a single seal is provided. 9.Device according to claim 1, in which the female part, from a centeraxis and radially outwards, comprises: an opening for transportation offluid, a hub symmetrically shaped around the opening, receiving groovesadapted to the guide pins of the corresponding male part, guide edgesand an external skirt, the hub, the receiving grooves and the guideedges contributing to the aligning effect when joining the female andthe male part.
 10. A device as in claim 1, further comprising arapid-release mechanism for each bolt.
 11. A device as in claim 1, inwhich the seal forms a single barrier.
 12. A device as in claim 1, inwhich the seal creates a plurality of barriers.
 13. A device as in claim4, in which there is a single pin-groove pair.
 14. A device as in claim13, in which the bolt is threaded.
 15. A device as in claim 13, in whichthe bolt is arranged with a bayonet fitting.